1. Field of the Invention
The present invention relates to a display driver for driving the display device according to a video signal.
2. Description of the Related Art
A liquid crystal display panel, an example of a display device, includes a plurality of gate lines extending in a horizontal direction of a two-dimensional screen and a plurality of source lines extending in a vertical direction of the two-dimensional screen. The gate lines and the source lines are arranged to intersect each other. A display cell taking charge of a pixel is formed at the intersection between each gate line and each source line. The liquid crystal display panel includes a source driver for applying gradation display voltages corresponding to the luminance levels of pixels expressed by an input video signal to the respective source lines, and a gate driver for applying a scan signal to the gate lines. As a source driver like this, one configured to individually take in a plurality of pieces of display data for a horizontal synchronizing period into a plurality of latches and apply the gradation display voltages corresponding to the pieces of display data taken into the respective latches to the source lines has been proposed (for example, see Japanese Patent Application Laid-Open No. 2004-301946). Such a source driver shifts the take-in timing of the display data by each of the foregoing latches by using delay circuits using element delays of inverter elements, whereby concentration of currents flowing into the source lines is prevented to prevent noise occurring in such a state.
With the delay circuits using the element delays of the inverter elements described above, the delay mounts vary due to manufacturing variations, ambient temperature, etc. The timing at which the gradation display voltages are applied to the display cells via the source lines therefore may fail to coincide with the timing at which the scan signal is applied to the display cells via the gate lines, possibly producing uneven luminance within the display screen.